Which battle in 1634 was a decisive Imperial-Spanish victory?

The Battle of Nördlingen was the decisive Imperial-Spanish victory of 1634.

Fought on 5–6 September 1634, the battle pitted an Imperial and Spanish army against Swedish and German forces near Nördlingen in Bavaria. The Imperial-Spanish side was led by Cardinal-Infante Ferdinand and Ferdinand of Hungary, while the opposing army included Gustav Horn and Bernhard of Saxe-Weimar. The battle began as the Protestant coalition tried to relieve the Swedish garrison inside Nördlingen.

The Swedish-German army attacked repeatedly, especially against the strongly defended Albuch heights, but Spanish veterans and Imperial reinforcements held their positions. When the Protestant army began withdrawing, the Imperial cavalry turned the retreat into a rout. Gustav Horn was captured, and the Swedish army suffered roughly 12,000–14,000 casualties or prisoners, compared with about 3,500 on the victorious side.

Nördlingen effectively destroyed Swedish power in southern Germany and encouraged several German states to seek the Peace of Prague. It also helped prompt France to intervene directly against the Habsburgs. It should not be confused with the First Battle of Nördlingen, fought in 1634’s earlier campaign context in some older references.